46 . III. DIST. CHAR. Mode. 



In most of these instances, the further decay of the 

 veliquium and the consequent loss of its form, ap- 

 pear to be prevented merely by seclusion from the 

 atmospheric air.f 



3. CONVERSION (Conversio}. The separation 

 and loss of the more volatile principles of the origi- 

 nal body are frequently followed by a total cliatigc, 

 arising from a new combination^ff in those which 

 remain,, the substance thus produced being chemi- 

 cally distinct from, yet still retaining the structure 

 of the recent subject. 



Obs. The bodies most liable to this change are 



J- The peculiar nature and state of the inclosing substance will 

 doubtless sometimes conduce to the more effectual conservation of 

 such bodies, even when no actual impregnation of mineral particles 

 has taken place. Thus, the saline quality of the earth, in which 

 the bones so frequent in America are mostly found, is supposed to 

 have contributed to their preservation; and it is obvious, that the 

 putrefaction of the flesh of the Rhinoceros at)ove mentioned, could 

 only have been prevented by the congelation of the soil, in which 

 ft was buried, 



ff This must possess the structure of the original; otherwise 

 not to be considered as an extraneous fossil, (v. Note -j-. p. 43.) 



A conversion or chemical change, in the principles of organic 

 matter, when it has become a subject of the fossil kingdom, must 

 take place in process of time, in every instance ; but the term here, 

 is only applied to those bodies capable of preserving their internal 

 fabric, under such spontaneous alteration. 



Conservata that have undergone the process of conversion, occur 

 in the same kind of soils, as those that have not suffered a chemical 

 change (111. 2.). 



